World's smallest atomic clock goes on sale

Emma Woollacott, 3rd May 2011

Well, it's certainly annoying when your wristwatch doesn't keep perfect time. But there's a solution - yes, the world's smallest atomic clock is now available commercially, for only $1,500.

The matchbook-sized device is 100 times smaller than its commercial predecessors, and has been created by a team of researchers at Symmetricom Inc. Draper Laboratory and Sandia National Laboratories. It also needs just one-hundredth of the power, at only 100 milliwatts.

"It's the difference between lugging around a device powered by a car battery and one powered by two AA batteries," says Sandia lead investigator Darwin Serkland.

The clock works by counting the frequency of electromagnetic waves emitted by cesium atoms struck by a tiny laser beam.

Unfortunately, it won't be much of a substitute for that Rolex on your wrist - it doesn't actually display the time. But, say its creators, it has a wide range of uses.

Miners or divers, blocked by natural barriers from GPS signals, could plan precise operations with remote colleagues, because their timing would deviate from each other by less than one millionth of a second in a day.

The device could also be invaluable in using electromagnetic interference to stop telephone signals from detonating IEDs. While GPS signals would be blocked by interference, the atomic clock would still function.

The work was funded by DARPA.

"Because few DARPA technologies make it to full industrial commercialization for dual-use applications, this is a very big deal," says Gil Herrera, director of Sandia's Microsystems and Engineering Sciences Application center. "CSAC now is a product with a data sheet and a price."